Recent discoveries of electronic correlations in the twisted bilayer graphene (TBG), including correlated insulators [1]}, superconductivity [2]}, (quantum) anomalous Hall state [3]}, [4]} and others [5]}, [6]}, [7]}, [8]}, [9]}, [10]}, [11]}, [11]}, [13]}, [14]}, [15]}, [16]}, [17]}, [18]}, [19]}, [20]}, [21]}, [22]}, [23]}, [24]}, [25]}, [26]}, [27]}, [28]}, have generated enthusiasm among both experimentalists and theorists. It is becoming clear that the interplay between band topology and strong electronic interactions plays an essential role in understanding the remarkable phenomena [29]}, [30]}, [31]}, [32]}, [33]}, [34]}, [35]}, [36]}, [37]}, [38]}, [39]}, [40]}, [41]}, [42]}, [43]}, [44]}, [45]}, [46]}, [47]}, [48]}, [49]}, [50]}, [51]}, [52]}, [53]}, [54]}, [55]}, [56]}, [57]}, [58]}, [59]}, [60]}. However, many of the key questions, such as the exact ground states and the mechanism of superconductivity, still remain open.
